During the last five years, the Switching and Access Solutions Group o
f Lucent Technologies has made a considerable investment in domain eng
ineering. Much of this work has been motivated by a desire to reduce t
he software development interval. The use of domain engineering has he
lped to decrease considerably the time required to design and implemen
t software. In this paper; we examine four domain engineering projects
. We find that each project was guided by two sets of criteria for suc
cess-one addressing the concerns of good engineering practice and the
other addressing the special needs of technology transfer. The five cr
itical attributes of new technology identified by E. M. Rogers's Diffu
sion of Innovations-relative advantage, compatibility complexity, tria
lability, and observability-play an important role in domain engineeri
ng. In the projects we examine, attention to these attributes helped s
hape the final products and the processes by which they were created.